Circulatory and respiratory assist devices, such as cardiopulmonary bypass circuits (CPB), ventricular assist devices (VAD's) and blood membrane (ECMO's) are routinely used in cardiac surgery and to support patient impaired physiological functions. Inadequate biocompatibility of foreign surfaces contacting the patient's blood contributes to the activation of blood proteolytic systems such as coagulation, complements, fibrinolysis and also activates cellular blood components. This can result in a potentially life threatening systemic inflammatory response. BIOMEC has developed a novel and promising type of surfactant polymer coating (SPC), which can be used to substantially improve the biocompatibility of these devices. As a result of our Phase II SBIR effort, BIOMEC has improved the process of surfactant polymer synthesis, which allows for reproducible production of larger volumes of the material necessary for extensive coating and testing. In vitro performance of SPC coated blood pumps in human blood was compared to the uncoated pumps (negative control) and to heparin coated pumps (positive control). We demonstrated that SPC prevents surface platelet and neutrophils adsorption with efficacy at least equivalent and generally better than heparin coating. The surfactant coating also significantly lowers the hemolysis rate in comparison to heparin-coated pumps. Preliminary toxicity testing and in vivo studies (pig model) indicate that the coating is biologically safe and does not affect the pump hemodynamic performance. An additional advantage of SPC over heparin coatings is its extreme simplicity of application to existing commercial devices, and hence its low cost. In this project phase we propose to continue biological safety evaluation of SPC according to FDA requirements. Further, upon approval of an Investigational Device Exemption we will conduct a pilot clinical study to conclusively demonstrate the in vivo safety and effectiveness of SPC coated cardiopulmonary bypass circuit. As the result of these efforts, BIOMEC will have developed an effective yet inexpensive blood compatible coating for blood contacting devices.